Commit Graph

98 Commits

Author SHA1 Message Date
Reid Kleckner
4b70bfc905 Begin adding docs and IR-level support for the inalloca attribute
The inalloca attribute is designed to support passing C++ objects by
value in the Microsoft C++ ABI.  It behaves the same as byval, except
that it always implies that the argument is in memory and that the bytes
are never copied.  This attribute allows the caller to take the address
of an outgoing argument's memory and execute arbitrary code to store
into it.

This patch adds basic IR support, docs, and verification.  It does not
attempt to implement any lowering or fix any possibly broken transforms.

When this patch lands, a complete description of this feature should
appear at http://llvm.org/docs/InAlloca.html .

Differential Revision: http://llvm-reviews.chandlerc.com/D2173

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197645 91177308-0d34-0410-b5e6-96231b3b80d8
2013-12-19 02:14:12 +00:00
Matt Arsenault
59d3ae6cdc Add addrspacecast instruction.
Patch by Michele Scandale!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194760 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-15 01:34:59 +00:00
Juergen Ributzka
623d2e618f [Stackmap] Add AnyReg calling convention support for patchpoint intrinsic.
The idea of the AnyReg Calling Convention is to provide the call arguments in
registers, but not to force them to be placed in a paticular order into a
specified set of registers. Instead it is up tp the register allocator to assign
any register as it sees fit. The same applies to the return value (if
applicable).

Differential Revision: http://llvm-reviews.chandlerc.com/D2009

Reviewed by Andy

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194293 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-08 23:28:16 +00:00
Rafael Espindola
19794da02c Remove linkonce_odr_auto_hide.
linkonce_odr_auto_hide was in incomplete attempt to implement a way
for the linker to hide symbols that are known to be available in every
TU and whose addresses are not relevant for a particular DSO.

It was redundant in that it all its uses are equivalent to
linkonce_odr+unnamed_addr. Unlike those, it has never been connected
to clang or llvm's optimizers, so it was effectively dead.

Given that nothing produces it, this patch just nukes it
(other than the llvm-c enum value).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193865 91177308-0d34-0410-b5e6-96231b3b80d8
2013-11-01 17:09:14 +00:00
Andrew Trick
2ddc56dec8 Add new calling convention for WebKit Java Script.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193812 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-31 22:12:01 +00:00
Shuxin Yang
69bd41dfe3 Revert r193251 : Use address-taken to disambiguate global variable and indirect memops.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193489 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-27 03:08:44 +00:00
Shuxin Yang
8e3851a6eb Use address-taken to disambiguate global variable and indirect memops.
Major steps include:
 1). introduces a not-addr-taken bit-field in GlobalVariable
 2). GlobalOpt pass sets "not-address-taken" if it proves a global varirable 
    dosen't have its address taken.
 3). AA use this info for disambiguation. 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193251 91177308-0d34-0410-b5e6-96231b3b80d8
2013-10-23 17:28:19 +00:00
Peter Collingbourne
1e3037f0be Implement function prefix data as an IR feature.
Previous discussion:
http://lists.cs.uiuc.edu/pipermail/llvmdev/2013-July/063909.html

Differential Revision: http://llvm-reviews.chandlerc.com/D1191

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190773 91177308-0d34-0410-b5e6-96231b3b80d8
2013-09-16 01:08:15 +00:00
Andrea Di Biagio
5768bb8d77 Add function attribute 'optnone'.
This function attribute indicates that the function is not optimized
by any optimization or code generator passes with the 
exception of interprocedural optimization passes.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189101 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-23 11:53:55 +00:00
Charles Davis
ac226bbf45 Target/X86: Add explicit Win64 and System V/x86-64 calling conventions.
Summary:
This patch adds explicit calling convention types for the Win64 and
System V/x86-64 ABIs. This allows code to override the default, and use
the Win64 convention on a target that wants to use SysV (and
vice-versa). This is needed to implement the `ms_abi` and `sysv_abi` GNU
attributes.

Reviewers:

CC:

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186144 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-12 06:02:35 +00:00
Michael Gottesman
2253a2f52f Added support for the Builtin attribute.
The Builtin attribute is an attribute that can be placed on function call site that signal that even though a function is declared as being a builtin,

rdar://problem/13727199

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@185049 91177308-0d34-0410-b5e6-96231b3b80d8
2013-06-27 00:25:01 +00:00
Diego Novillo
77226a03dc Add a new function attribute 'cold' to functions.
Other than recognizing the attribute, the patch does little else.
It changes the branch probability analyzer so that edges into
blocks postdominated by a cold function are given low weight.

Added analysis and code generation tests.  Added documentation for the
new attribute.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182638 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-24 12:26:52 +00:00
Stephen Lin
456ca048af Add CodeGen support for functions that always return arguments via a new parameter attribute 'returned', which is taken advantage of in target-independent tail call opportunity detection and in ARM call lowering (when placed on an integral first parameter).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179925 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-20 05:14:40 +00:00
Kostya Serebryany
8eec41fc77 Unify clang/llvm attributes for asan/tsan/msan (LLVM part)
These are two related changes (one in llvm, one in clang).
LLVM: 
- rename address_safety => sanitize_address (the enum value is the same, so we preserve binary compatibility with old bitcode)
- rename thread_safety => sanitize_thread
- rename no_uninitialized_checks -> sanitize_memory

CLANG: 
- add __attribute__((no_sanitize_address)) as a synonym for __attribute__((no_address_safety_analysis))
- add __attribute__((no_sanitize_thread))
- add __attribute__((no_sanitize_memory))

for S in address thread memory
If -fsanitize=S is present and __attribute__((no_sanitize_S)) is not
set llvm attribute sanitize_S


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176075 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-26 06:58:09 +00:00
Bill Wendling
143d46476c Implement the NoBuiltin attribute.
The 'nobuiltin' attribute is applied to call sites to indicate that LLVM should
not treat the callee function as a built-in function. I.e., it shouldn't try to
replace that function with different code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175835 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-22 00:12:35 +00:00
Kostya Serebryany
ab39afa9d9 [tsan/msan] adding thread_safety and uninitialized_checks attributes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174864 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-11 08:13:54 +00:00
Bill Wendling
95ce4c2ffb Initial submission for the attribute group feature.
Attribute groups are of the form:

  #0 = attributes { noinline "no-sse" "cpu"="cortex-a8" alignstack=4 }

Target-dependent attributes are represented as strings. Attributes can have
optional values associated with them. E.g., the "cpu" attribute has the value
"cortex-a8".

Target-independent attributes are listed as enums inside the attribute classes.

Multiple attribute groups can be referenced by the same object. In that case,
the attributes are merged together.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174493 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-06 06:52:58 +00:00
Michael Gottesman
a2de37c897 Added LLVM Asm/Bitcode Reader/Writer support for new IR keyword externally_initialized.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174340 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-05 05:57:38 +00:00
Bill Wendling
114baee1fa Add the IR attribute 'sspstrong'.
SSPStrong applies a heuristic to insert stack protectors in these situations:

* A Protector is required for functions which contain an array, regardless of
  type or length.

* A Protector is required for functions which contain a structure/union which
  contains an array, regardless of type or length.  Note, there is no limit to
  the depth of nesting.

* A protector is required when the address of a local variable (i.e., stack
  based variable) is exposed. (E.g., such as through a local whose address is
  taken as part of the RHS of an assignment or a local whose address is taken as
  part of a function argument.)

This patch implements the SSPString attribute to be equivalent to
SSPRequired. This will change in a subsequent patch.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173230 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-23 06:41:41 +00:00
James Molloy
67ae135759 Add a new attribute, 'noduplicate'. If a function contains a noduplicate call, the call cannot be duplicated - Jump threading, loop unrolling, loop unswitching, and loop rotation are inhibited if they would duplicate the call.
Similarly inlining of the function is inhibited, if that would duplicate the call (in particular inlining is still allowed when there is only one callsite and the function has internal linkage).



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170704 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20 16:04:27 +00:00
Bill Wendling
3defc0bfa6 Add back support for reading and parsing 'deplibs'.
This is for backwards compatibility for pre-3.x bc files. The code reads the
code, but does nothing with it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168779 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-28 08:41:48 +00:00
Bill Wendling
efd08d413c Remove the dependent libraries feature.
The dependent libraries feature was never used and has bit-rotted. Remove it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168694 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 09:55:56 +00:00
Michael Ilseman
15c13d3e63 Fast-math flags for LLVM IR parsing and printing
Added in the ability to read LLVM IR text that contains fast-math flags as a sequence of capital letters separated by spaces in any order. Added in the printing of the fast-math flags in a canonical order, and don't print the other flags when 'fast' is specified, as 'fast' implies all the others.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168645 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 00:42:44 +00:00
Quentin Colombet
9a419f656e Change ForceSizeOpt attribute into MinSize attribute
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167020 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-30 16:32:52 +00:00
Elena Demikhovsky
3575222175 Special calling conventions for Intel OpenCL built-in library.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166566 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-24 14:46:16 +00:00
Nadav Rotem
e743942bc8 Add the "ForceSizeOpt" attribute.
Patch by Quentin Colombet <qcolombet@apple.com>

Original description:
"""
The attached patch is the first step to have a better control on Oz related optimizations.
The Oz optimization level focuses on code size, thus I propose to add an attribute called ForceSizeOpt.
"""



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166422 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-22 17:33:31 +00:00
Micah Villmow
e53d6051b7 Add in support for SPIR to LLVM core. This adds a new target and two new calling conventions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164948 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-01 17:01:31 +00:00
Chad Rosier
581600bfc3 [ms-inline asm] Enumerate the InlineAsm dialects and rename the nsdialect to
inteldialect.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163231 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-05 19:00:49 +00:00
Chad Rosier
36547343ab [ms-inline asm] Emit the (new) inline asm Non-Standard Dialect attribute.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163181 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-05 00:08:17 +00:00
Chad Rosier
4e2132e7ae [ms-inline asm] Remove the Inline Asm Non-Standard Dialect attribute. This
implementation does not co-exist well with how the sideeffect and alignstack
attributes are handled.  The reverts r161641.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@163174 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-04 22:29:45 +00:00
Bill Wendling
32811bef95 Change the linker_private_weak_def_auto' linkage to linkonce_odr_auto_hide' to
make it more consistent with its intended semantics.

The `linker_private_weak_def_auto' linkage type was meant to automatically hide
globals which never had their addresses taken. It has nothing to do with the
`linker_private' linkage type, which outputs the symbols with a `l' (ell) prefix
among other things.

The intended semantic is more like the `linkonce_odr' linkage type.

Change the name of the linkage type to `linkonce_odr_auto_hide'. And therefore
changing the semantics so that it produces the correct output for the linker.

Note: The old linkage name `linker_private_weak_def_auto' will still parse but
is not a synonym for `linkonce_odr_auto_hide'. This should be removed in 4.0.
<rdar://problem/11754934>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162114 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-17 18:33:14 +00:00
Chad Rosier
249d670dd0 [ms-inline asm] Add a new Inline Asm Non-Standard Dialect attribute.
This new attribute is intended to be used by the backend to determine how
the inline asm string should be parsed/printed. This patch adds the 
ia_nsdialect attribute and also adds a test case to ensure the IR is
correctly parsed, but there is no functional change at this time.

The standard dialect is assumed to be AT&T.  Therefore, this attribute
should only be added to MS-style inline assembly statements, which use
the Intel dialect.  If we ever support more dialects we'll need to
add additional state to the attribute.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161641 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-10 00:00:22 +00:00
Hans Wennborg
ce718ff9f4 Extend the IL for selecting TLS models (PR9788)
This allows the user/front-end to specify a model that is better
than what LLVM would choose by default. For example, a variable
might be declared as

  @x = thread_local(initialexec) global i32 42

if it will not be used in a shared library that is dlopen'ed.

If the specified model isn't supported by the target, or if LLVM can
make a better choice, a different model may be used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159077 91177308-0d34-0410-b5e6-96231b3b80d8
2012-06-23 11:37:03 +00:00
Bill Wendling
0f96817d01 'unwind' is a keyword, not an instruction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149898 91177308-0d34-0410-b5e6-96231b3b80d8
2012-02-06 21:02:43 +00:00
Kostya Serebryany
164b86b439 Extend Attributes to 64 bits
Problem: LLVM needs more function attributes than currently available (32 bits).
One such proposed attribute is "address_safety", which shows that a function is being checked for address safety (by AddressSanitizer, SAFECode, etc).

Solution:
- extend the Attributes from 32 bits to 64-bits
- wrap the object into a class so that unsigned is never erroneously used instead
- change "unsigned" to "Attributes" throughout the code, including one place in clang.
- the class has no "operator uint64 ()", but it has "uint64_t Raw() " to support packing/unpacking.
- the class has "safe operator bool()" to support the common idiom:  if (Attributes attr = getAttrs()) useAttrs(attr);
- The CTOR from uint64_t is marked explicit, so I had to add a few explicit CTOR calls
- Add the new attribute "address_safety". Doing it in the same commit to check that attributes beyond first 32 bits actually work.
- Some of the functions from the Attribute namespace are worth moving inside the class, but I'd prefer to have it as a separate commit.

Tested:
"make check" on Linux (32-bit and 64-bit) and Mac (10.6)
built/run spec CPU 2006 on Linux with clang -O2.


This change will break clang build in lib/CodeGen/CGCall.cpp.
The following patch will fix it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148553 91177308-0d34-0410-b5e6-96231b3b80d8
2012-01-20 17:56:17 +00:00
Rafael Espindola
b3c4e26dc5 Remove last references to hotpatch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141057 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-04 03:08:43 +00:00
Rafael Espindola
25456ef74c Add the returns_twice attribute to LLVM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141001 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-03 14:45:37 +00:00
Bill Wendling
e6e8826870 Initial commit of the 'landingpad' instruction.
This implements the 'landingpad' instruction. It's used to indicate that a basic
block is a landing pad. There are several restrictions on its use (see
LangRef.html for more detail). These restrictions allow the exception handling
code to gather the information it needs in a much more sane way.

This patch has the definition, implementation, C interface, parsing, and bitcode
support in it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137501 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-12 20:24:12 +00:00
Bill Wendling
dccc03b242 Add the 'resume' instruction for the new EH rewrite.
This adds the 'resume' instruction class, IR parsing, and bitcode reading and
writing. The 'resume' instruction resumes propagation of an existing (in-flight)
exception whose unwinding was interrupted with a 'landingpad' instruction (to be
added later).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136589 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-31 06:30:59 +00:00
Bill Wendling
10c6d12a9f Revert r136253, r136263, r136269, r136313, r136325, r136326, r136329, r136338,
r136339, r136341, r136369, r136387, r136392, r136396, r136429, r136430, r136444,
r136445, r136446, r136253 pending review.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136556 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-30 05:42:50 +00:00
Eli Friedman
ff03048c13 LangRef and basic memory-representation/reading/writing for 'cmpxchg' and
'atomicrmw' instructions, which allow representing all the current atomic
rmw intrinsics.

The allowed operands for these instructions are heavily restricted at the
moment; we can probably loosen it a bit, but supporting general
first-class types (where it makes sense) might get a bit complicated,
given how SelectionDAG works.

As an initial cut, these operations do not support specifying an alignment,
but it would be possible to add if we think it's useful. Specifying an
alignment lower than the natural alignment would be essentially
impossible to support on anything other than x86, but specifying a greater
alignment would be possible.  I can't think of any useful optimizations which
would use that information, but maybe someone else has ideas.

Optimizer/codegen support coming soon.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136404 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-28 21:48:00 +00:00
Bill Wendling
772fe17a6d Merge the contents from exception-handling-rewrite to the mainline.
This adds the new instructions 'landingpad' and 'resume'.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136253 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-27 20:18:04 +00:00
Eli Friedman
47f3513dd5 Initial implementation of 'fence' instruction, the new C++0x-style replacement for llvm.memory.barrier.
This is just a LangRef entry and reading/writing/memory representation; optimizer+codegen support coming soon.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@136009 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-25 23:16:38 +00:00
Chris Lattner
424545e950 remove asmparser support for the old getresult instruction, which has been subsumed by extractvalue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133247 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-17 06:57:15 +00:00
Chris Lattner
6b7c89ee09 stop accepting begin/end around function bodies in the .ll parser, this isn't pascal anymore.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133244 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-17 06:42:57 +00:00
Chris Lattner
f3a789d931 Remove old backwards compatibility support from the parser for autoupgrading
the old malloc/free instructions, and for 'sext' and 'zext' as function 
attributes (they are spelled signext/zeroext now), and support for result
value attributes being specified after a function.

Additionally, diagnose invalid attributes on functions with an error message
instead of an abort in the verifier.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133229 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-17 03:16:47 +00:00
John McCall
3a3465b71d Add a new function attribute, nonlazybind, which inhibits lazy-loading
optimizations when emitting calls to the function;  instead those calls may
use faster relocations which require the function to be immediately resolved
upon loading the dynamic object featuring the call.  This is useful when it
is known that the function will be called frequently and pervasively and
therefore there is no merit in delaying binding of the function.

Currently only implemented for x86-64, where it turns into a call through
the global offset table.

Patch by Dan Gohman, who assures me that he's going to add LangRef documentation
for this once it's committed.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133080 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-15 20:36:13 +00:00
Rafael Espindola
fc2bb8c444 Replace the -unwind-tables option with a per function flag. This is more
LTO friendly as we can now correctly merge files compiled with or without
-fasynchronous-unwind-tables.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132033 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-25 03:44:17 +00:00
Bill Wendling
5d7a5a4f53 Revert r129235 pending a vetting of the EH rewrite.
--- Reverse-merging r129235 into '.':
D    test/Feature/bb_attrs.ll
U    include/llvm/BasicBlock.h
U    include/llvm/Bitcode/LLVMBitCodes.h
U    lib/VMCore/AsmWriter.cpp
U    lib/VMCore/BasicBlock.cpp
U    lib/AsmParser/LLParser.cpp
U    lib/AsmParser/LLLexer.cpp
U    lib/AsmParser/LLToken.h
U    lib/Bitcode/Reader/BitcodeReader.cpp
U    lib/Bitcode/Writer/BitcodeWriter.cpp



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129259 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-10 23:18:04 +00:00
Bill Wendling
d7bb295d22 Beginning of the Great Exception Handling Rewrite.
* Add a "landing pad" attribute to the BasicBlock.
* Modify the bitcode reader and writer to handle said attribute.

Later: The verifier will ensure that the landing pad attribute is used in the
appropriate manner. I.e., not applied to the entry block, and applied only to
basic blocks that are branched to via a `dispatch' instruction.

(This is a work-in-progress.)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129235 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-10 00:04:27 +00:00